1. Field of the Invention
The present invention relates to a letter input apparatus and method which use a control dial input apparatus.
2. Description of the Related Art
In a case of inputting a letter on a menu screen by using a control dial input apparatus, there have been only three operating functions of the control dial input apparatus, namely, an upward direction revolution, a downward direction revolution and a dial press-down. Therefore, as shown in FIG. 3, it has been impossible to input a letter in a two dimensional fashion and, as shown in FIG. 2, it has been necessary that each letter is inputted by using one dimensional menu. FIG. 2 shows an operation carried out when letters of operation carried out when letters of "invention" are to be input. In FIG. 2, in a case when, for example, a third letter example, a third letter "V" is to be inputted after a first letter "I" and a second letter "N" are inputted, the control dial input apparatus has to be revolved to change over a letter displayed on a menu display from "A" to "V" through "B", "C", "D", . . . , "U" in an alphabetical order, and then the dial is pressed down to select the "V".
Instead of using the control dial input apparatus, there have been some apparatus for inputting a letter in a two dimensional fashion, as shown in FIG. 3, by using two dimensional input apparatus such as a cross key, a track ball and the like. However, although a display of the two dimensional input apparatus is easy to be looked, there is a problem that a space for it to be installed becomes larger and at the same time it is time consuming for operation. Therefore, as for a portable apparatus, the control dial input apparatus capable of realizing space saving has been used in many cases.
Kinds of letters to be inputted amount to about 140 in kinds of letters including a numeral, a symbol, an alphabet, Japanese letters called "hiragana" and the like. Therefore, when the letter is input by using only the one dimensional menu, a problem has occurred that it takes much time and trouble in selecting a letter.